Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Details

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Recent Financing Transactions Recent Financing Transactions - NPC (Details) - Nevada Power Company [Member] - USD ($) $ in Millions	Aug. 31, 2018	May 31, 2018	Apr. 30, 2018
Line of Credit [Member] \| Secured credit facility, $400 million, expiring June 2021 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 400
NVE Holdings [Member] \| NPC General and Refunding Mortgage Notes, Series BB [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 575
Debt Instrument, Interest Rate, Stated Percentage			2.75%
NVE Holdings [Member] \| NPC General and Refunding Mortgage Notes, Series O [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		6.50%
Debt Instrument, Repurchase Amount		$ 325
NVE Holdings [Member] \| NPC General and Refunding Mortgage Notes, Series S [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Debt Instrument, Repurchase Amount	$ 500